Feb. 8, 2011 -- The FDA has approved an injectable drug called Makena to reduce the risk of preterm delivery before 37 weeks in pregnant women who have had at least one premature birth.

Makena, or hydroxyprogesterone caproate, was approved under the federal agency's accelerated approval regulations, which allows drugs that show promise to get to the marketplace quickly.

FDA says in a news release that Makena is not meant to be used in women with a multiple pregnancy, such as a twin pregnancy, or other risk factors for preterm birth.

FDA Rule Should Make Makena Available Faster

Under the FDA's accelerated approval rules, the manufacturer, Bedford, Mass.-based Hologic Inc., must conduct additional research to demonstrate its efficacy and show it has a clinical benefit.

The company says it does not yet know when Makena will be available. According to the FDA, an international trial is under way aimed at learning if there also is improvement in the outcome of babies born to women given Makena, such as reducing the number of babies who do not survive or who suffer serious health problems shortly after birth.

“Preterm birth is a significant public health issue in the United States,” says Sandra Kweder, MD, deputy director of the FDA's Office of New Drugs. “This is the first drug approved by the FDA that is indicated to specifically reduce this risk.”

Makena: Weekly Injections

The FDA says a health care provider would give Makena once weekly by injection into the hip and that treatment should begin between 16-21 weeks of pregnancy.

The FDA says it reviewed data on the safety and efficacy of the drug in a randomized, double-blind clinical trial that included 463 women aged 16 to 43 who were pregnant with a single fetus and who had a history of a prior spontaneous preterm birth.

It says that among women treated with Makena, 37% delivered before 37 weeks, compared to 55% of women not taking the drug.

Another study evaluated the development of children born to mothers enrolled in the controlled trial. In that study, children aged 2 1/2 to 5 reached similar developmental targets regardless of the mother's treatment.

The drug will be studied in follow-up research that will end in about 2018. That study is expected to include 580 to 750 infants.

The FDA originally approved hydroxyprogesterone caproate under the trade name Delalutin in 1956 for use in pregnant women with threatened miscarriage. The FDA says the original manufacturer requested that Delalutin be withdrawn from the market in 2000 for reasons not related to safety.

Alan Fleischman, MD, senior vice president and medical director of the March of Dimes, says in a news release that Makena will give hope to women who have delivered babies too soon that “their next child will have a better chance at a healthy start in life.”

He says women who have previously had a baby born prematurely should check with their doctors to see if Makena is appropriate for them, because it is “not for everyone.”

The statement says a study by the March of Dimes, the National Institutes of Health, and the CDC, using 2002 data, estimated that if all women eligible for the progesterone injections received them, about 10,000 spontaneous premature births might be prevented annually.